Recognizing Ocular Surface Disease in Your Office
Early detection of dry eye helps improve patient satisfaction.
By Stephen C. Pflugfelder, MD
I see the entire spectrum of dry eye patients in my practice, and I begin treatment of these patients the same way. I ask about their symptoms and run a standard battery of dry eye tests, which include a tear film breakup test (TFBUT), inspecting the cornea and conjunctiva, performing staining tests (either using fluorescein or lis-samine stains) and finally administering a Schirmer's test.
Therapies for Treating Dry Eye
I use a severity-based treatment algorithm based on the 2007 report of the International Dry Eye Workshop (DEWS). The algorithm ranks dry eye severity on a scale of 1 through 4 — with level 1 being mild and 4 being the most severe (Table 1).
I tailor my therapies based on the severity level. So, usually by level 2 severity, they require anti-inflammatory therapy. From there, I may recommend additional therapies based on the level of severity. Surgery is an accepted treatment for some types of level 4. For example, if the patient has a corneal ulcer, it may require amniotic membrane transplantation or a tarsorrhaphy, which is sewing the lid together partially. This treatment can be temporary or permanent depending on the severity of the dry eye (Table 2).
Here are some steps your patients can take to improve their environment and help ease dry eye symptoms. ■ Use a humidifier ■ Position desk away from an air draft ■ Position computer display monitor at or below eye level to keep the eye from opening too widely ■ Use artificial tears before flying and several times during every flight |
Table 2. Treatment recommendations by severity level |
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Level 1: Education and environmental/dietary modifications; elimination of offending systemic medications; artificial tear substitutes, gels/ointments; eye lid therapy Level 2: If Level 1 treatments are inadequate, add: anti-inflammatories; tetracyclines (for meibomianitis, rosacea); punctal plugs; secretogogues; moisture chamber spectacles Level 3: If Level 2 treatments are inadequate, add: serum; contact lenses; permanent punctal occlusion Level 4: If Level 3 treatments are inadequate, add: systemic anti-inflammatory agents; surgery (lid surgery, tarsorrhaphy, mucus membrane, salivary gland, amniotic membrane transplantation) Modified from: International Task Force Guidelines for Dry Eye; 2006 |
Other Dry Eye Occurrences
If the OSD is on the more severe side or the patient is experiencing systemic complaints due to arthritis or arthralgia, or if they have skin rash or other manifestations of autoimmune disease (such as dry mouth), these symptoms are important to recognize. I recommend a blood test to check for autoantibodies that are specific for autoimmune conditions or I have the patient visit their primary care doctor or rheumatologist. I will work with their doctors and make suggestions about treatment options. I would prefer to manage the treatment, at least from the ocular perspective.
Autoimmune issues are age independent, but on the whole, dry eye occurrences increase with age. Age may be the biggest risk factor in dry eye. The majority of younger patients who appear with moderate to dry eye have an autoimmune disease. In addition, many people use oral medications that cause dry eye. Antidepressants are the number one type of medication followed by antihistamines and antispasmodics. The medications that doctors are least likely to alter are the antidepressants. Whenever possible, if there's a less drying agent, I point it out to the patient and suggest they contact the doctor who prescribed the medication.
Dry eye is commonly associated with systemic autoimmune diseases, such as rheumatoid arthritis and progressive systemic sclerosis due to defects in the immune system that inadequately regulate immune reactions or cause excessive response to normal environmental stress.
Posterior blepharitis also causes dry eye. Most patients who have this condition complain of irritation because of tear dysfunction and an unstable tear film. I treat them more or less the same as a dry eye patient but add treatments that are good for their lid margin such as oral doxycycline, fish oil and topical azithromycin (Azasite, Inspire Pharmaceuticals).
With refractive surgery patients, you should identify dry eye patients preoperatively. Many patients seek refractive surgery because they're contact lens intolerant due to irritation or redness. Some complain of irritation due to their contact lenses. They may have irritation without the contact lenses.
Others may have minimal complaints but show evidence of tear dysfunction — maybe a very rapid TFBUT or corneal or conjunctival epithelial disease or lid margin disease. We diagnose them as having a tear dysfunction problem. If they have primary lid margin disease, I use oral doxycycline, fish oil and Azasite. I don't find lid scrubs to be very helpful in this particular patient population.
If a patient is contemplating LASIK, you shouldn't perform surgery until the OSD is adequately treated. You have to treat the OSD first. The goal is to achieve a healthy tear and a healthy ocular surface. Creating a healthy ocular surface may take 1-3 months. If at the end of 3 months the patient has not improved, he/she is not a good candidate for LASIK, but may be a candidate for surface ablation. If the patient has improved satisfactorily, he can opt to have LASIK as long as he understands that he will experience dry eye afterwards. The goal is to ensure that patients are no worse than they were preop, although there's a small chance they'll have dry eye forever.
Patients undergoing cataract surgery who have chosen a multifocal lens are treated in the same manner as LASIK patients. Both multifocal IOLs and dry eye decrease contrast sensitivity. Patients who receive multifocals and have dry eye, especially with corneal epithelial disease or an unstable tear film, aren't very happy with their IOL outcomes. You must treat the dry eye prior to surgery in order to make the experience a positive one. If you're performing cataract surgery with a monofocal lens, you want the patient to be in good enough shape that you can get good quality IOL power calculation. You need to guarantee that they won't become severely worse to the point that the OSD limits their visual recovery.
Backing Away from BAK
If a patient has preexisting dry eye, he can experience toxicity from benzalkonium chloride (BAK) fairly quickly. In my experience, if he has a normal tear film to begin with, it may take anywhere from a few months to a year to see toxicity from BAK. Each person is different and you need to judge the status of his ocular status during the initial visit. While only a small percentage of patients experience toxicity from BAK, for those that do, it can be quite severe.
BAK-induced OSD sometimes look like severe dry eye or the eye can appear all red. Sometimes the epithelial disease that forms on the cornea is more diffuse than in dry eye, affecting the whole cornea. It can certainly make preexisting dry eye worse, and in patients without dry eye, can cause significant cornea, conjunctival and lid margin problems.
If you think the OSD is due to BAK, decrease the number of BAK-containing drops or eliminate them. Some patients can use oral therapy for glaucoma. I recommend carbonic anhydrase inhibitors such as diamox. I then use preservative-free artificial tears and if their pressure can handle it, I prescribe a preservative-free steroid preparation and cyclosporine ophthalmic emulsion (Restasis, Allergan, Inc.) or cyclosporine.
There are some problems with diagnosing BAK complications. Some doctors lack the clinical awareness or may examine the patient after they have received topical anesthetic drops or applanation topography that may cause corneal epithelial disease that masks the problem. Additionally, a patient may not fully convey the problem or may not mention that he's having difficulty with his current drop. Once you've seen toxicity from BAK happen enough, you become more aware that BAK can be a problem. I think doctors need to be aware of the signs (rapid TFBUT, corneal and conjunctival dye staining and lid margin and conjunctival redness) and pay attention to the symptoms the patient is complaining about.
In an ideal world, all doctors would use BAK-free preparations but cost comes into play, and there are some generic glaucoma prescriptions available OTC (but they all contain BAK). A patient's level of insurance may affect their prescription, and not everyone can be treated with a BAK-free formulation, but BAK-free should be the goal.
Stephen C. Pflugfelder, MD, is a professor, James and Margaret Elkins Chair and director of the Ocular Surface Center at the Cullen Eye Institute, Department of Ophthalmology, Baylor College of Medicine, Houston, TX. He has clinical and research interests in cornea and ocular surface diseases. He is particularly interested in the mechanisms inducing ocular surface inflammation in response to desiccating stress. He serves on the Editorial Boards of the journals American Journal of Ophthalmology, Cornea, Investigative Ophthalmology and Visual Science and The Ocular Surface.